page file

[Perris Calderon]

delhan...welcome to the board...stick around, and don't just be the visitor.

yours is a great first post...putting into emphasis that sometimes the things we say are hard to follow.

the best configuration for you is the system managed page file...you'll never have to worry about it.

now, here's a very simplified idea of what the page file does...so that everyone can understand the necessity of the very concept, and also understand the benign nature of this function;

I prefer the term "swap file"

when you load a very sophisticated program, there are tons of features that you will never use...but they are necessary for some users...these features would tie ram up, if it were not for the swap file...the OS makes the least accessed features of a program available to swap, so if you need more ram, it's availability will not affect your use of the program

the swap file mearly creates addresses for this information, and does not write to disc till you're running low on ram...this is why the page file always has activity, even when you have tons of ram available

this is one of the things that are meant when you hear the experts tell you that XP manages ram better then 3rd party programs

here's the interesting thing, and this'll show the benign nature of the page file;

even when ram is written to disc, the information is still in ram, and ready to be accessed as ram...if you use the feature before it's erased...it'll then be moved to a more important staure and not becomea swapped file at all...it's not until you've run out of ram, and are accessing new features that require ram, that xp will erase the information that has transferred to disc.

now, even when you do run low in ram, and the ram is written to disc, you still shouldn't see any performance hit, as it's your least accessed information that's written to disc...probably features you will never use in that session

the only time you'll use the paged information, is when you've simply run out of ram...even though you might have reached the point where your ram is being written to disc...and then, only when you therefore go to a feature that has not been accessed recently

ha, I just read what I wrote, and it still sounds complicated, so I'll work in putting this in a more easily understood set of pros...

 

[delhan]

yes ) sorry but i will agree
will wait for your next simplification effort of your lectures

the only thing i got is that windows are able to determine which info is more frequently accessed so place it that way in either ram or swap file so that is accessible faster (like the defrag software). And also learned that lots of useless crap (propably) are loaded to RAM (apart from the default 70mb that winXP uses from my 512 RAM)



Note 1
in another winxp pro pc i have 1GB ram and 2 HDDs . I use a 550min-550max page-file setting for both drives. I use Adobe Photoshop (giant ram and disk eater while editing for prepress), CorelDRAW and macromedia Flash, Dreamweaver and Director. Pc runs literaly sweetly .... no problems at all (?)

thats an experimental pf setting i used by my experience from win98se and kept it for months now without problems ....

Note 2
In another pc i have 512MB RAM and pf settings are 770min-770max in boot partition and 770min-770max in the partition with the most free space (three partitions on this drive , pagefiles only in two) Is that a good setting ? i usualy play 3D games in this pc and maybe sometimes i may explore 3DSmax .... very rarely use it for professional reasons ...

Thanks

 

[allan]

TwoZig

If you need the crash dump feature then there are problems bigger than the pagefile quesiton. And that would require that vm is on the boot drive, which most users prefer not to do. I have mine set to NONE.

 

[2z]

Originally posted by allan
TwoZig If you need the crash dump feature then there are problems bigger than the pagefile quesiton. And that would require that vm is on the boot drive, which most users prefer not to do. I have mine set to NONE.

By default its set to complete dump, & not many users know its there or what its for !!! My concern is that users are buying large amounts of cheap RAM & thinking your advice is sound & by not informing people about disabling this feature YOU are actually setting people up for errors !!!!!!!
Not once do mention recovery settings on YOUR THREAD

 

[allan]

Not a bad point, thank you for mentioning it. Still, the worst that will happen if the pagefile is not set on the boot drive to the size you suggest AND the system wants to creat a crash dump is that there will be a message to the user that he doesn't have a large enough pagefile on the bootdrive.

So I'm not really "setting anyone up for errors" as you put it. Nothing bad can happen - the dump just won't be created. But still, you make a valid point about my not mentioning it and again, I appreciate you pointing it out.

 

[2z]

if you dont mind your system grinding to halt & losing all the your work every time XP has a problem then thats OK,

However, if you completely remove the paging file from the boot partition, Windows cannot create a dump file (Memory.dmp) in which to write debugging information in the event that a kernel mode STOP error message occurs. This can lead to extended downtime if a debug procedure is necessary to troubleshoot the STOP error message.

 

[Goldy]

Hi All,
Another thing that Allan forgot to mention is that a perfect factory made harddrive lifespan is measured by the no. of times it can be wrote to/read from. So if you set your pagefile to static and do not have a lot of ram the PC reads and writes to this part of the HDD over and over again and quite frequently. This can not be good for the life expectancy if it keeps reading/writing to the same part of the HDD??????

 

[allan]

Actually that's not the purpose of a memory dump. But I didn't come here to get into debates with all you experts, just to try to help some others who may need some assistance.

Anyway, I've already made an adjustment to the post on my site. Thanks again for pointing out the omission.

 

[2z]

That blows the partition theory right out of the water - only got 55 "googols" left.

 

[allan]

Goldy - ummmm - okay.

 

[Goldy]

I think that the most important piont in all this talk is that it all depends on what the PC Specs are. Amount of RAM being the most important. If some 1 is running XP on 128mb of RAM it would not be wise to restrict the pagefile, even with 256mb of RAM when your playing with large files e.g. DVD/MPEG it is not wise to ristrict your pagefile.

 

[jpennaro]

Soooo...... what´s the recipe for the pagefile?

PAGEFILE = 2*RAMSIZE ???

Is that ok?

I have 256 MB RAM..... what do you recomend?

 

[Perris Calderon]

with your configuration, 2x ram, expansion enabled to the full capacity of the disc

as far as allan saying memory dump is the only reason for a big page file, not true...program usage is the best reason for a big pagefile.

setting the system to allow expansion is the best setting if you intende on using of all your ram without a slow down...when the file is static, you will have a slow down when you do start to use all the ram...and that will happen ever more frequently as programmers write more and more sophisticated programs

 

[Perris Calderon]

ok...a better attempt at describing the page file...(memory dump withstanding)


xp would like you to always be able to launch another program

that pretty much sums up the function of the page file

when you are running a program with many features, xp starts mapping possible candidates of used ram that doesn't need to be used...now don't forget, all sophisticated programs have tons of features the majority of people just don't use, yet the features are written in for the few who will use them...(and these people aren't using other features in the program)

it decides which features are not neccessary by how long ago a feature was used.

when it decides that a feature is old enough, it creates an address for that ram information, but it does not write to disc yet...it's just creating an address

if that feature is used at any time during this mapping, that information is no longer a candidate for being swapped to the page file

nothing is written to disc, untill you are becoming closer to needing more ram

when something is finally written to disc, it is something you have not used for the longest period of time

then, that ram becomes available for a differant feature

however, the information is still in that ram, so if the feature happens to be accessed before the ram is claimed, it will remain in ram, and it will no longer be a candidate for a swap

so that's it

now, while the page file is big enough to keep you running smoothly, xp is very happy

if the page file is too small for your present needs, xp will try to expand the page file, and thereby, keep you running smoothely

a marvelous feature...dissabling this feature???? ha...a bright idea??? ha...who thought of this?

it's such a bad idea to dissable this feature

now, as far as lowering your page file...there is absolutely no gain to having a page file too small, and I'm still waiting for any proponent of lowering your page file to tell me the use of this...exactly what do you think is going to happen if you have an extra bit of hard drive?...anything at all?? faster box???less cpu usage???...what???no performance gain whatsoever...the extra gig you might gain by lowering your page file will serve you no other purpose...so let it serve page file purpose

there is, on the other hand a huge performance hit when xp is having trouble finding addresses if you've made the page file too small, so why would anyone want to do this?

there is absolutely no reason a person would want to lower a page file, unless they are running short on disc space, and need the room...and for this...fine...nessesity, and all that

so you see, when the swap file is working smoothely, you will probably not even notice the ram that was written to disc, as it is the features you are not likely to use that are affected

if the page file is static, and can't expand to xps needs, xp will page to other areas, and xp will not be able to have the discrimination it needs of what ram to page

ok, let me know if that's easy to follow

 

[Goldy]

Quite right! Dealer
bigger if anything is my XP-eriance too.